I can see those happening if we get more vacation worlds. Like maybe each new vacation world can have a skill or recipe, etc...that a sim can only learn if they meet a local from that area or if they travel down to that world.
I did like what they did for Jungle Adventure and how the locals all that their own style, the new dances, etc....I want that game pack so badly and want to see other worlds that helps add something new. Maybe the next one can be tropical based like maybe a Caribbean country or maybe a world inspired by Samoa or Hawaii.